triangular distribution Archives - Infinity is Really Big

May 1, 2019January 11, 2020

Curtate Expectation of Life

Studying for Exam LTAM, Part 1.9

Image by Clker-Free-Vector-Images from Pixabay

Means of random variables can be thought of as centers of mass. If the random variable is continuous, think of the region under the graph of its probability density function (PDF) as a thin sheet of metal with constant density. The mean will be at the center of mass

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April 30, 2019May 8, 2019

Curtate Future Lifetime Random Variable

Studying for Exam LTAM, Part 1.8

Photo by Annie Spratt on Unsplash

When somebody asks you how old you are, how do you answer? Are you like most people? Do you give your age from your previous birthday? Or do you get extra-precise and say something like “I am 21 years, 5 months, and 1 week old”?

If you answer … Read the rest

April 18, 2019April 23, 2019

Measures of Spread in Survival Models

Studying for Exam LTAM, Part 1.6

Image by Gerd Altmann from Pixabay

One of the main lessons students should get out of any statistics course is the fact that quantitative data can be described with summary measures.

Data come with a wide variety of “locations”, “spreads”, and “shapes”. These words refer to the nature of the distribution of a … Read the rest

April 10, 2019April 23, 2019

Triangular Survival Models

Studying for Exam LTAM, Part 1.5

An example of a triangular distribution probability density function (PDF).

An important principle in mathematical modeling is to start simple. For example, if you have a situation where a linear function matches the trend in your data, go ahead and use a linear function rather than, for example, a quadratic function.

If a … Read the rest